100 Days of Science-- #25 Color Changing Slime

My boys could not have been more thrilled when I mentioned that we were going to be making some slime that changed color this week.  We have made lots of versions of slime before and it's always a huge hit with the boys.

In order to make our slime I knew we'd need liquid starch, school glue, and to make it change color I ordered this thermochromatic pigment.

With all our ingredients assembled, we set to work.  In our "science experiment bowl" (yes, we keep a cheap dollar store bowl set aside just for these types of things!) we mixed together equal parts glue and starch.  We added 3 teaspoons of the pigment to give it a nice color.

We talked about what thermochromatic meant and how it worked. Alec immediately told us that thermo was temperature like thermometer and I explained that chromatic meant color.  So this meant our slime would change color based on temperature. 

1/2 way through mixing and Evan decided we needed a photo since it looked like brains or intestines. 
It still needed a touch more starch here so the slime would hold it's shape just a bit better.

Once we had a good consistency they divided the slime into three piles and each took some to play with on our junky cookie sheets we keep around just for this type of activity.

Evan went to get the hair dryer to warm up his slime and we watched it begin to turn yellow where it had warmed up.

As soon as it began cooling of it turned pink again.

Ian liked to heat his up with the dryer and then put the cold water bottle on top.  It immediately changed color.

The younger two boys decided to head outside into the sun to see if hey could get their slime to change color that way.

They noticed that as the cookie sheets warmed up the backside of the slime changed to yellow and if they moved/ mixed it up they occasionally got a slightly orange tint before it all turned back to pink again.

Evan realized that if he trailed small, skinny pieces of slime around the tray those small pieces would warm up and turn yellow.

It was a lot of fun and they played for a good hour or so before I called them in to finish up the rest of our schoolwork.

You might also like this post; 15 Different slime and play dough recipes for sensory play

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  1. What a fun activity. I like the way they took the initiative to find ways to heat and cool it.

  2. Oh goodness....I'm not sure I want to share this with my Carly! She and her bestie have seriously been a little too creative some days trying to make slime.

    Shelly | The Queen in Between

    1. Oh I know what you mean. My kids set up a slime shop in the driveway last summer making a new color or type of slime just about every time I turned around.

  3. My daughter (who is reading over my shoulder) wants to know where to get the powder. I went back up and clicked through to Amazon to show her. She LOVES slime - and I really don't. But I do love the science aspect of this project!

    1. Yeah, there are tons of color combos to choose from with the powder. I am not a hue fan of slime but do enjoy the science aspect of it. I often have the kids do these sorts of experiments outside.

  4. I had 6 - 12 year old girls here for a sleepover on Friday night, They were playing with slime abd would have loved to try this! #FabFridayPost

  5. AI love this recipe. It's cheap and cheerful and with lots of fun! But we don't have that kind of starch over here. :( I'm need to cry now. ;) xx

    1. If you can find Borax I have made slime using warm water, borax, and school glue.. there are LOTS of slime recipes around using all sorts of household liquids and I think as long as you can find the color changing pigments you could make color changing slime.

  6. Oh wow this looks fab - think my twins would love this! :) #AnythingGoes


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